AP2 orbit & ear

orbital cavity margins

roof

floor

medial wall

lateral wall

orbital cavity bones

sphenoid

frontal

ethmoid

lacrimal

maxilla

zygomatic

optic canal is where _ and opthalmic artery pass

optic nerve

what nerves pass the superior orbital fissure

abducens

oculomotor

trochlear

opthalmic branch of trigeminal

lacrimal groove

indentation in lacrimal bone

creates passage from orbit → opening of lacrimal duct

3 layers of optic nerve

dura

arachnoid

pia mater

3 layers of globe of eye

fibrous layer

vascular layer

nervous layer

fibrous layer of eye contains

sclera and cornea

(superficial)

vascular layer of eye consists of

uvea (iris, ciliary body, choroid)

nervous layer of globe has what

sensory receptors (rods/cones)

inner globe of eye contains?

lens

virtreous humor

lens in eye role

focuses light onto retina to create a sharp image

sclera role

“white of eye”

insertion site for extraocular and intrinsic eye muscles

cornea vasculature and sensitivity to touch

avascular

sensitive to touch

iris function and role

pigmented portion that regulates light entry

muscles constrict (parasympathetic) or dilate (sympathetic) the pupil

ciliary body role

anchors lens

contains ciliary muscles

secretes virteous humor

choroid role

thin middle layer of posterior eye

highly vascular

constriction of the eye is associated with para vs. sympathetic?

parasympathetic

main artery supplying blood to the eye

central retinal artery

pathway of blood into the eye

internal carotid artery → ophthalmic artery → central retinal a

cornea function

providing protection and initial refraction of light into eye

6 muscles respondible for eye movement

1. superior oblique m

2. inferior oblique m

3. superior rectus m

4. inferior rectus m

5. medial rectus m

6. lateral rectus m

3 nerves responsible for eye movement

1. oculomotor

2. trochelar

3. abducens

role of superior oblique m

intorsion

depression

abduction

“down and out muscle”

inferior oblique m role

extortion

elevation

abduction

superior rectus m

primary elevator

inferior rectus m

primary depressor

medial rectus m

primary adductor

lateral rectus m

primary adductor

LR6SO4R3

lateral rectus = CN 6

superior oblique = CN 4

remaining = CN 3

intorsion definition

rolling eye medially

extorsion definition

rolling eye laterally

controls elevation and retraction of the upper lid

levator palpebrae superioris m

passage of tears

tears leave eye through upper and lower punctum

enters canaliculi

upper and lower canaliculus converges to syphon tears → lacrimal sac

orbicularis oculi m contracts to push tears down → nasal lacrimal duct

auricle function

cartilaginous external portion of ear

external auditory canal

passageway to tympanic membrane and external auditory meatus

the _ separates the external auditory meatus from the middle ear

tympanic membrane

tympanic membrane function

receives sound waves, resulting in vibration

3 ossicles of middle ear

malleus

incus

stapes

role of 3 ossicles of middle ear

transmits sound waves to cochlea

what is the canal connecting middle ear to nasopharynx?

auditory tube (AKA eustacian tube)

purpose of auditory tube (eustacian tube)

keep pressure inside the middle ear same as outside

what 2 muscles block the tympanic cavity

tensor palati m

levator palati m

tensor palati m role

opens auditory tube when swallowing to regulate pressure

levator palati m role

elevates soft palate during swallowing to prevent food from entering nasopharynx

what are constrictor muscles

3 muscles that help propel food from oral cavity → esophagus